JP6048102B2 - Information processing system - Google Patents

Description

  The present invention relates to an information processing system, and more particularly to an information processing system for estimating a network bandwidth.

  There is known a network bandwidth estimation system that estimates a physical bandwidth and / or an available bandwidth (hereinafter referred to as an available bandwidth) in an IP (Internet Protocol) network (see, for example, Patent Document 1 and Non-Patent Document 1). The available bandwidth is a free bandwidth obtained by excluding traffic flowing in the IP network from the physical bandwidth of the IP network. For example, when the physical bandwidth is 100 Mbps and the traffic is 30 Mbps, the available bandwidth is 100 Mbps-30 Mbps = 70 Mbps. In the network bandwidth estimation system, when data is transmitted beyond the available bandwidth, congestion may occur in the network, and transmission data may be lost or transmission data may be delayed.

  Accordingly, when a network application using an IP network (for example, a data distribution system such as a moving image or a voice) performs communication, if the network is congested, the user's quality of experience is lowered. For this reason, the importance of the network application controlling transmission data using the information on the available bandwidth estimated by the network bandwidth estimation system described above is increasing.

JP2008-258877

Vinay J. Ribeiro, Rudolf H. Riedi, Richard G. Baraniuk, JiriNavratil and Les Cottrell, “pathChirp: Efficient Available Bandwidth Estimation for Network Paths,” in Proc. Of Passive and Active Measurement Workshop 2003.

  Here, in the network bandwidth estimation system of Non-Patent Document 1 described above, first, the transmission apparatus transmits a plurality of estimation packets having the same packet size while decreasing the transmission interval exponentially. Subsequently, the reception device receives the estimation packet transmitted by the transmission device, and measures the reception interval of the estimation packet.

  When the transmission apparatus decreases the transmission interval exponentially, the transmission rate of the estimation packet increases exponentially. Then, when the transmission rate of the estimation packet exceeds the usable bandwidth, the reception interval measured by the reception device increases more than the transmission interval at which the transmission device transmits the estimation packet. Therefore, a delay time is calculated by subtracting the transmission interval at which the transmission device has transmitted the estimation packet from the reception interval at which the reception device has received the estimation packet, and whether or not the calculated delay time exceeds a preset threshold value. Thus, the estimation packet (delay start packet) that starts increasing in comparison with the transmission interval of the estimation packet is detected. Then, the available bandwidth is calculated (estimated) by dividing the packet size (constant) by the transmission interval based on the detected delay start packet.

  As described above, in the network bandwidth estimation system of Non-Patent Document 1 described above, information on the received estimation packet (jth estimation packet (j> 1: j is a natural number)) and the previous estimation received. The delay time is calculated based on the information of the packet for use (j-1st estimation packet). However, the delay time in the vicinity of the delay start packet described above is very small, and may be affected by noise or the like that is not related to the band depending on the network state. For example, the reception time of the estimation packet may fluctuate due to a delay caused by fluctuations in radio wave quality in a wireless environment. As a result, there is a possibility that a plurality of the delay start packets described above may be detected, and there is a problem that the estimation accuracy of the available bandwidth is deteriorated by detecting an erroneous delay start packet.

  Moreover, in the network band estimation system of Patent Document 1 described above, a technique using a statistical method is described in order to prevent deterioration of estimation accuracy of the available band. Specifically, the transmission device transmits different packet pairs (two packets) with different transmission intervals, and the reception device measures the reception intervals of the received packet pairs and stores them in the storage unit. And the location where the tendency of a transmission interval and a reception interval changes is statistically calculated using the some transmission interval and reception interval which were memorize | stored in the memory | storage part.

  However, since the network bandwidth estimation system of Patent Document 1 described above estimates the available bandwidth using a statistical method, the available bandwidth can be obtained only with a packet pair transmitted from the transmission device to the reception device at a single timing. There is a risk that the estimation accuracy of the bandwidth may be lowered, and it takes time to improve the estimation accuracy of the available bandwidth.

  Therefore, an object of the present invention is to provide an information processing system that can solve the problem that it takes time to improve the estimation accuracy of the available bandwidth.

In order to achieve the above object, an information processing system according to an aspect of the present invention includes:
A transmission apparatus comprising estimation packet transmitting means for transmitting a plurality of estimation packets having packet sizes set in advance to a reception apparatus connected via a network at a predetermined transmission interval; and the reception apparatus; With
The receiving device is:
An estimation packet receiving means for receiving the estimation packet transmitted from the estimation packet transmitting means;
Packet information acquisition means for acquiring the reception time and packet size of the estimation packet received by the estimation packet reception means;
Reception of estimation packets transmitted back and forth based on the reception times of the estimation packet received first and last among the plurality of estimation packets received by the estimation packet receiving means A delay start packet detecting means for detecting an estimation packet whose interval starts to change as a delay start packet;
Bandwidth calculation means for calculating the bandwidth of the network using the packet size of the delay start packet detected by the delay start packet detection means;
It takes the composition of having.

An information processing apparatus according to another aspect of the present invention
Estimating packet receiving means for receiving the estimating packet from a transmitting apparatus that transmits a plurality of estimating packets having packet sizes set in advance to a receiving apparatus connected via a network at a preset transmission interval When,
Packet information acquisition means for acquiring, as packet information, the reception time and packet size of the estimation packet received by the estimation packet reception means;
Of the plurality of estimation packets received by the estimation packet receiving means, based on the packet information of the estimation packet received first and last, the estimation packets transmitted back and forth with each other Delay start packet detecting means for detecting an estimation packet whose reception interval starts to change as a delay start packet;
Bandwidth calculation means for calculating the bandwidth of the network using the packet size of the delay start packet detected by the delay start packet detection means;
It takes the composition of having.

In addition, an information processing method according to another aspect of the present invention includes:
Receiving the estimation packet from a transmission device that transmits a plurality of estimation packets having packet sizes set in advance to a reception device connected via a network at a preset transmission interval;
Obtaining the reception time and packet size of the received estimation packet as packet information,
Based on the packet information of the first and last received estimation packets among the plurality of received estimation packets, the estimation interval at which the reception interval with the estimation packets transmitted back and forth starts to change Detect the packet as a delayed start packet,
A bandwidth is calculated using the packet size of the detected delay start packet.
Take the configuration.

Moreover, the program which is the other form of this invention is:
In the information processing device,
Estimating packet receiving means for receiving the estimating packet from a transmitting apparatus that transmits a plurality of estimating packets having packet sizes set in advance to a receiving apparatus connected via a network at a preset transmission interval When,
Packet information acquisition means for acquiring, as packet information, the reception time and packet size of the estimation packet received by the estimation packet reception means;
Of the plurality of estimation packets received by the estimation packet receiving means, based on the packet information of the estimation packet received first and last, the estimation packets transmitted back and forth with each other Delay start packet detecting means for detecting an estimation packet whose reception interval starts to change as a delay start packet;
Bandwidth calculating means for calculating a bandwidth using the packet size of the delay start packet detected by the delay start packet detecting means;
It is a program for realizing.

  According to the present invention, network bandwidth estimation processing can be realized quickly and with high accuracy.

It is a figure which shows the example for detecting a change point. It is a block diagram which shows the outline of a structure of the information processing system in 1st Embodiment of this invention. It is a block diagram which shows the structure of a transmitter. It is a block diagram which shows the structure of a receiver. It is a functional block diagram which shows the structure of the information processing system in this invention. It is a figure for demonstrating the example of a packet information management table. It is a figure which shows an example of a packet number and delay time. It is a figure which shows an example of a packet number and a packet delay accumulation value. It is a flowchart for demonstrating a transmission process. It is a flowchart for demonstrating a band estimation process. It is a functional block diagram which shows the structure of the information processing system in 2nd Embodiment of this invention. It is a flowchart for demonstrating a band estimation process. It is a functional block diagram which shows the structure of the information processing system in 3rd Embodiment of this invention.

<First Embodiment>
First, in order to facilitate understanding of the embodiment of the present invention, an example of a network bandwidth estimation system related to the present invention will be described. In a network bandwidth estimation system, a bandwidth is obtained by calculating a change point of a parameter y (x) depending on x of an estimation packet received by a reception device with respect to a predetermined parameter x of the estimation packet transmitted by the transmission device. Estimate As a set of x, y (x), for example, (x, y) = (transmission rate, difference between reception rate and transmission rate) or (x, y) = (difference between transmission interval, reception interval and transmission interval) Etc.

  For example, in Non-Patent Document 1 described above, a plurality of estimation packets having the same packet size are transmitted, and the reception interval is transmitted from the transmission interval of the transmitted estimation packet and the reception interval of the received estimation packet. An estimation packet (delay start packet) that starts increasing with respect to the interval is detected. Then, the available bandwidth is estimated using the information of the detected delay start packet.

  The delay start packet detection process will be specifically described below. First, a packet delay accumulated value Q (i) (i is a natural number) representing the accumulated value of the transmission delay time of the estimation packet is defined as shown in Equation 1.

In Equation 1, T _s (i) indicates the transmission time of the i-th transmitted estimation packet, and T _r (i) indicates the reception time of the i-th transmitted estimation packet. That is, the accumulated packet delay value Q (i) in Equation 1 is a value obtained by subtracting the reception time of the estimation packet transmitted first (first) from the reception time of the i-th transmission packet (first and i The value obtained by subtracting the transmission time of the first estimation packet from the transmission time of the i-th estimation packet (the transmission interval of the first and i-th estimation packets). And the difference between the two.

  In Non-Patent Document 1 described above, the value of Q (i) -Q (i-1) (the increase amount of the packet delay accumulated value when the i-th estimation packet is received) exceeds a preset threshold value. It is determined that a delay has occurred in the transmitted estimation packet.

  Since the packet delay accumulated value Q (i) is calculated by the difference between the reception interval and the transmission interval of the estimation packet, it increases as the reception interval becomes larger than the transmission interval. An increase in the reception interval compared with the transmission interval indicates that congestion or the like occurs in the communication network 13 and a delay occurs. That is, when the increase amount of the packet delay accumulated value when the i-th estimation packet is received exceeds the threshold, the i-th estimation packet exceeds the transmission rate (usable bandwidth) of the communication network 13. Therefore, the available bandwidth can be estimated by calculating the transmission rate R (i) of the i-th estimation packet. The transmission rate R (i) is calculated by the following equation (2).

  P (i) in Equation 2 indicates the packet size of the i-th estimation packet. That is, the transmission rate R (i) is calculated by a value obtained by dividing the packet size of the i-th estimation packet by the transmission interval of the i-th and (i + 1) -th estimation packets. In addition, Q (i) in Equation 1 is rewritten as Equation 3 below.

Here, ΔT _r (j) represents the reception interval between the (j−1) th and jth estimation packets, and ΔT _s (j) represents the transmission interval between the (j−1) th and jth estimation packets. Represents. It is assumed that T _r (0) = T _r (1) and T _s (0) = T _s (1). At this time, Q (i) -Q (i-1) is expressed by the following equation (4) from equation (3).

  That is, Q (i) -Q (i-1) is expressed as (i-1) th and i from the reception interval of the (i-1) th and ith estimation packets (estimation packets preceding and following each other). It is represented by a value obtained by subtracting the transmission interval of the first estimation packet. By the way, the value of equation (4) is very small, and is easily affected by noise or the like when detecting an estimation packet in which a delay starts to occur. For example, as shown in FIG. 1, an estimation packet 302 before the estimation packet 301 (appropriate estimation packet) that originally starts to be delayed may be erroneously detected. Since the estimation packet 302 is an estimation packet transmitted before the estimation packet 301, the network bandwidth (available bandwidth) estimated based on the estimation packet 302 may be underestimated. As a result, a transmission rate lower than the optimum transmission rate is set, and the packet transfer efficiency decreases.

  Further, for example, due to the influence of noise or the like, an estimation packet 303 after the estimation packet 301 may be erroneously detected as shown in FIG. Since the estimation packet 303 is an estimation packet transmitted after the estimation packet 301, the bandwidth of the network estimated based on the estimation packet 303 may be overestimated. As a result, a transmission rate higher than the optimum transmission rate is set, and congestion or the like occurs in the network. As described above, when the band is estimated based on the value of Equation 4, the estimation accuracy of the network band is likely to be affected by noise or the like.

  Based on the above band estimation system, a first embodiment of the present invention will be described with reference to FIGS. 2 to 8 are diagrams for describing the configuration of the information processing system according to the first embodiment. 9 and 10 are diagrams for explaining the operation of the information processing system.

[Constitution]
FIG. 2 is a block diagram showing the configuration of the information processing system 1 according to the first embodiment of the present invention. As illustrated in FIG. 2, the information processing system 1 includes a transmission device 11, a reception device 12, and a communication network 13 (network). The transmitter 11 transmits a plurality of estimation packets (for example, test packets) to the receiver 12 in order to estimate the available bandwidth of the communication network 13. The reception device 12 receives a plurality of estimation packets transmitted from the transmission device 11, and performs an estimation process of the available bandwidth of the communication network 13 based on the received estimation packets.

  Next, the configuration of the transmission device 11 and the reception device 12 (information processing device) will be described with reference to FIGS. FIG. 3 is a block diagram illustrating a configuration example of the transmission device 11. As illustrated in FIG. 3, the transmission device 11 includes a calculation unit 21, a memory 22, a communication unit 23, and a storage unit 24.

  The computing unit 21 is configured by, for example, a CPU (Central Processing Unit). The calculation unit 21 reads the program stored in the storage unit 24 and executes the program using the memory 22 as a work area, thereby executing various functions for controlling the transmission device 11. The functional configuration of the calculation unit 21 will be described later with reference to FIG. The communication unit 23 transmits the estimation packet instructed to be transmitted by a transmission control unit 52 described later to the receiving device 12 via the communication network 13.

  FIG. 4 is a block diagram illustrating a configuration example of the receiving device 12. As illustrated in FIG. 4, the reception device 12 includes a calculation unit 31, a memory 32, a communication unit 33, and a storage unit 34. Note that the configuration of the reception device 12 in FIG. 4 is the same as that of the transmission device 11 in FIG.

  The calculation unit 31 executes various functions for controlling the receiving device 12 by reading the program stored in the storage unit 34 and executing the program using the memory 32 as a work area. The functional configuration of the calculation unit 31 will be described later with reference to FIG. The communication unit 33 receives the estimation packet transmitted from the transmission device 11. Then, the receiving device 12 performs a bandwidth estimation process for the communication network 13 based on the received estimation packet.

  Next, with reference to FIG. 5, details of each configuration of the transmission device 11 and the reception device 12 will be described. FIG. 5 is a block diagram illustrating a functional configuration example of the transmission device 11 and the reception device 12. The calculation unit 21 of the transmission device 11 includes an estimation packet generation unit 51 and a transmission control unit 52 (estimation packet transmission unit) by executing a program. In addition, the calculation unit 31 of the reception device 12 executes a program, so that a reception control unit 61 (estimation packet reception unit), a packet information acquisition unit 62 (packet information acquisition unit), a storage control unit 63, A change point calculation unit 64 (delay start packet detection unit) and a band calculation unit 65 (band calculation unit) are included.

  First, transmission processing of the estimation packet of the transmission device 11 will be described. First, the estimation packet generator 51 of the transmission device 11 generates a plurality of estimation packets. For example, the estimation packet generator 51 sequentially sets packet numbers, and generates n (n is a natural number) estimation packets whose packet size increases linearly as the packet number increases. That is, the packet size of the i-th (0 <i ≦ n) estimation packet is expressed by the following equation (5).

The number as shown in Equation 5, i-th packet size P _i of the estimated packet is first packet size P ₁ of the estimation packet of (first), estimation packet from the first to the (i-1) -th The packet increase size ΔP (that is, the product of the number of estimation packets (i−1) and the packet increase size ΔP) can be calculated. Note that the packet size calculation method of the estimation packet generator 51 is not limited to the above equation 5, and any information may be used as long as it is information necessary for the bandwidth estimation process of the communication network 13. For example, the estimation packet generation unit 51 may determine the packet size of the estimation packet so as to decrease the packet size as the packet number increases. Further, the estimation packet generator 51 may make the packet size of the estimation packet constant regardless of the packet number.

  Subsequently, the transmission control unit 52 acquires the transmission time. The transmission control unit 52 acquires the transmission time of the i-th estimation packet so that the transmission interval between the estimation packets that are sequentially transmitted becomes a predetermined transmission interval. That is, the i-th estimation packet transmission interval is constant (for example, 1 millisecond) as shown in Equation 6 below.

  Subsequently, the transmission control unit 52 waits until the acquired transmission time, and transmits the estimation packet to which the transmission time is added to the reception device 12 via the communication unit 23 and the communication network 13 when the transmission time is reached. To do. Then, the transmission control unit 52 repeats the estimation packet transmission process described above until all the estimation packets generated by the estimation packet generation unit 51 are transmitted. In this way, the transmission control unit 52 transmits a plurality of estimation packets having packet sizes set in advance to the receiving device 12 connected via the communication network 13 at a preset transmission interval. Thereby, the transmission device 11 can transmit an estimation packet for estimating the available bandwidth of the communication network 13 to the reception device 12.

  Next, the band estimation process of the receiving device 12 will be described. First, the reception control unit 61 receives the estimation packet transmitted from the transmission device 11 via the communication unit 33. Subsequently, the packet information acquisition unit 62 acquires the packet information of the estimation packet received by the reception control unit 61. The packet information includes, for example, the packet number of the estimation packet, the packet size, the transmission time, the reception time, and the like. Note that the packet information is not limited to these, and may be any information as long as it is information necessary for the bandwidth estimation process.

  Subsequently, the storage control unit 63 stores the packet information acquired by the packet information acquisition unit 62 in the storage unit 34 (or the memory 32). For example, as illustrated in FIG. 6, the storage control unit 63 stores a packet information management table 81 that manages packet information of each estimation packet in the storage unit 34.

  Subsequently, the reception control unit 61 determines whether all the estimation packets transmitted from the transmission device 11 have been received. Specifically, the reception control unit 61 determines whether all estimation packets have been received based on the number of estimation packets stored in advance or the number of estimation packets notified from the transmission device 11. judge. If all the estimation packets have not been received, the reception control unit 61 repeats the estimation packet reception process. On the other hand, when all the estimation packets are received, the change point calculation unit 64 calculates the change point. Below, the calculation method of a change point is demonstrated.

  If the change point at which the delay time required for transmission of the estimation packet starts increasing in the communication network 13 is k, the above equation 4 can theoretically be expressed as the following equation 7.

P _j represents the packet size (byte) of the j-th estimation packet. C is a constant and represents, for example, a physical band (bps). That is, the value of ΔT _r (j) −ΔT _s (j) is 0 from the first estimation packet to the kth estimation packet. Also, the value of ΔT _r (j) −ΔT _s (j) is the kth estimation packet from the packet size of the estimation packet of the current packet number j from the (k + 1) th to the jth estimation packet. The value obtained by subtracting the packet size is divided by the physical bandwidth. The value of ΔT _r (j) −ΔT _s (j) is the time taken to transmit packet size data that cannot be transferred within a predetermined time due to congestion in the communication network 13 (ie, delay time). Represents. Since the packet size P increases linearly as shown in Equation 5, Equation 7 increases linearly as shown in FIG. Note that C in Equation 7 is not limited to a physical band, but may be an available band or a wireless effective band.

  Further, from the equation (7), the packet delay accumulated value Q (i) of the above equation (3) can be rewritten by the following equation (8).

  That is, the packet delay accumulated value Q (i) is the sum of the difference from the packet size difference between the kth and (k + 1) th estimation packets to the difference between the packet size differences between the kth and ith estimation packets. Calculated by dividing by band C. Here, when i is substituted for j and Equation 8 is expanded for i> k, Equation 9 is obtained.

  If Q (i)> 0, that is, i satisfying i> k, the change point k can be obtained by substituting into the above equation. Since the increase amount of the packet size of the estimation packet is constant, the packet increase size ΔP is a constant. Here, the packet delay accumulated value Q (i) that is least affected by noise or the like is the packet delay accumulated value Q (n) referring to the last (n-th) estimation packet transmitted from the transmission device 11. . This is because the last estimation packet is set to a packet size that is large enough to cause congestion in the communication network 13, so that noise or the like may occur in the last estimation packet (for example, reception of the last estimation packet). This is because the influence on (time) is slightly different (congestion occurs regardless of the influence of noise or the like). Accordingly, when i = n is substituted into Equation 9 and the solution formula is used, the change point k at which the delay starts is calculated by Equation 10 below.

  Here, the packet delay accumulated value Q (n) is defined as the reception time of the first (first) estimation packet from the reception time of the last (n-th) estimation packet, as defined by the above-described equation (1). Subtracted value (reception interval of the first and last estimation packets) and value obtained by subtracting the transmission time of the first estimation packet from the transmission time of the last estimation packet (transmission interval of the first and last estimation packets) And the difference between the two. Note that the first estimation packet is set to a sufficiently small packet size so that congestion does not occur in the communication network 13, and thus is less susceptible to noise and the like as the last estimation packet.

  That is, the change point calculation unit 64 detects a delay start packet based on the accumulated packet delay value that represents the accumulated value of the delay time for transmission of the calculated estimation packet. Therefore, the change point calculation unit 64 determines the reception interval of the estimation packets transmitted back and forth based on the packet information (for example, reception time) of the first and last estimation packets that are not easily affected by noise or the like. Since the estimation packet that starts to change can be detected as a delay start packet (change point is calculated), the delay start packet can be detected with high accuracy.

  When the change point calculation unit 64 calculates the change point using Equation 10, the bandwidth calculation unit 65 calculates (estimates) the available bandwidth of the communication network 13 based on the calculated change point. Specifically, the bandwidth calculation unit 65 calculates the available bandwidth of the communication network 13 using the following equation (11).

  Here, the value of the numerator in Equation 11 represents the packet size of the kth estimation packet (see Equation 5). In addition, the value of the denominator of Equation 11 represents the transmission interval (see Equation 6). That is, the available bandwidth B is calculated by dividing the packet size of the kth estimation packet by the transmission interval.

  Thereafter, when the reception control unit 61 receives all of the plurality of estimation packets transmitted from the transmission device 11, the packet information acquisition unit 62 acquires the packet information, the change point calculation unit 64 calculates the change point, Each process in which the calculation unit 65 calculates (estimates) the bandwidth of the communication network 13 is continued. Then, based on the available bandwidth calculated by the receiving device 12, a predetermined network application controls transmission data so that a delay does not occur (congestion does not occur in the communication network 13).

  In this way, when the estimation packet transmitted from the transmission device 11 is affected by noise or the like unrelated to the congestion of the communication network 13, the reception of the first and last estimation packets that are least affected by the noise or the like is received. Since the estimation packet whose delay starts is detected using each of the time and the transmission time, the estimation accuracy of the bandwidth of the communication network 13 can be improved.

[Operation]
Next, the operation of the information processing system 1 will be described with reference to FIGS. 9 and 10. FIG. 9 is a flowchart showing the operation of the transmission apparatus 11. FIG. 10 is a flowchart showing the operation of the receiving device 12.

  In the estimation packet transmission process of FIG. 9, first, the estimation packet generation unit 51 generates a plurality of estimation packets (step S1). For example, the estimation packet generation unit 51 generates n estimation packets whose packet size increases linearly as the packet number increases.

  Next, the transmission control unit 52 acquires the transmission time (step S2). For example, the transmission control unit 52 acquires the transmission time of the i-th estimation packet so that the transmission interval between the estimation packets that are sequentially transmitted becomes a predetermined transmission interval.

  Subsequently, the transmission control unit 52 waits until the transmission time acquired in the process of step S2 (step S3). And the transmission control part 52 transmits the packet for estimation which added the transmission time to the receiver 12 via the communication part 23 and the communication network 13 (step S4).

  Subsequently, the transmission control unit 52 determines whether all estimation packets have been transmitted (step S5). That is, the transmission control unit 52 determines whether all n estimation packets generated in the process of step S <b> 1 have been transmitted to the receiving device 12. If it is determined in step S5 that all transmission packets have not been transmitted (step S5: No), the process returns to step S2, and the transmission control unit 52 performs the (i + 1) th transmission. Get the transmission time of the trusted packet. And the process after step S3 is repeated.

  On the other hand, if it is determined in step S5 that all estimation packets have been transmitted (step S5: Yes), the estimation packet transmission process ends.

  Next, the band estimation process of the receiving device 12 will be described with reference to FIG. In the band estimation process of FIG. 10, first, the reception control unit 61 receives an estimation packet transmitted from the transmission device 11 (step S <b> 21). Subsequently, the packet information acquisition unit 62 acquires packet information (step S22).

  Subsequently, the storage control unit 63 stores the packet information acquired in the process of step S22 (step S23). Then, the reception control unit 61 determines whether or not all estimation packets have been received (step S24). If it is determined in step S24 that all estimation packets have not been received (step S24: No), the process returns to step S21, and the subsequent processes are repeated.

  On the other hand, when it is determined in step S24 that all estimation packets have been received (step S24: Yes), the change point calculation unit 64 calculates a change point (step S25). Since the calculation method of the change point has been described with reference to Equation 10, the description thereof will be omitted. Then, the bandwidth calculation unit 65 acquires packet information of the estimation packet indicated by the change point calculated in the process of step S25 (step S26). Specifically, the bandwidth calculation unit 65 acquires the packet size of the estimation packet detected by the change point calculation unit 64 based on the calculated change point.

  Finally, the bandwidth calculation unit 65 calculates an available bandwidth using the packet information acquired in the process of step S26 (step S27) (see Equation 11). After the process of step S27, the available bandwidth estimation process of the receiving device 12 ends.

  In this way, when the estimation packet transmitted from the transmission device 11 is affected by noise or the like, the reception time and transmission time of the first and last estimation packets that are least affected by noise or the like are used. Thus, since the estimation packet whose delay starts is detected and the band is estimated, the band estimation accuracy can be improved.

Second Embodiment
Next, a second embodiment of the present invention will be described with reference to FIG. 11 and FIG. FIG. 11 is a diagram for explaining the configuration of the information processing system. FIG. 12 is a diagram for explaining the operation of the information processing system. The second embodiment is different from the first embodiment in that a change point is calculated every time the receiving device 12 receives an estimation packet.

[Constitution]
First, the configuration of the information processing system 101 in the second embodiment will be described with reference to FIG. In addition, the same code | symbol is attached | subjected to what has the structure similar to the information processing system 1 in 1st Embodiment. That is, the information processing system 101 in FIG. 11 is different from the information processing system 1 in FIG. 5 in that the receiving device 12 includes the change point counting unit 111, and other configurations are the same as those in the information processing system 1 in FIG. is there.

  In the second embodiment, when the reception control unit 61 receives the estimation packet, the packet information acquisition unit 62 acquires the packet information of the estimation packet received by the reception control unit 61. Subsequently, the change point calculation unit 64 calculates a change point based on the packet information acquired by the packet information acquisition unit 62. Specifically, the change point calculation unit 64 includes the above-described Expression 10, the packet information (for example, reception time and transmission time) of the first estimation packet, and the last estimation packet (the estimation packet received immediately before). ) To calculate the change point.

  Next, the change point counting unit 111 records (counts) the number of times the same change point calculated by the change point calculation unit 64 is calculated. Then, the change point counting unit 111 determines whether or not the same change point is calculated more than a preset threshold value. The receiving device 12 repeats the above-described change point calculation process until the same change point is calculated to be equal to or greater than the threshold value. When the change point counting unit 111 determines that the same change point is calculated to be equal to or greater than the threshold, the change point counting unit 111 outputs the change point to the band calculating unit 65. Note that the change point counting unit 111 may record the number of times the same estimation packet based on the change point calculated by the change point calculating unit 64 is detected.

  Subsequently, the band calculating unit 65 acquires the change point output from the change point counting unit 111, and acquires packet information of the estimation packet detected by the change point calculating unit 64 based on the acquired change point. Then, the bandwidth calculation unit 65 calculates the available bandwidth based on the acquired packet information (specifically, the packet size) (Equation 11). As described above, in the information processing system 101, the change point calculation unit 64 receives the estimation packet received first and last among the plurality of received estimation packets every time the reception control unit 61 receives the estimation packet. The change point is calculated based on the reception time of (detects a delay start packet). Then, the change point counting unit 111 (bandwidth calculation means) counts the calculated number of times of the same change point (the number of detection of the same delay start packet), and when the same change point is calculated more than a preset number of times. The bandwidth calculator 65 calculates the bandwidth using the change point (packet size of the delay start packet). As a result, as in the information processing system 1 according to the first embodiment, the bandwidth is calculated before all the n estimation packets set in advance are received, so the highly accurate bandwidth can be estimated more quickly. be able to.

[Operation]
Next, with reference to FIG. 12, the band estimation process of the receiving device 12 in the second embodiment will be described. Note that steps S41 to S44, S46, and S47 of the band estimation process of FIG. 12 are the same as the processes of steps S21 to S23 and S25 to S27 of the band estimation process of FIG. . Further, the estimation packet transmission processing of the transmission device 11 has been described above with reference to FIG.

  In the band estimation process of FIG. 12, first, the reception control unit 61 receives an estimation packet (step S41). Subsequently, the packet information acquisition unit 62 acquires packet information (step S42). Subsequently, the storage control unit 63 stores the packet information acquired in the process of step S42 (step S43).

  And the change point calculation part 64 calculates a change point (step S44). Next, the change point counting unit 111 determines whether or not the same change point is calculated to be equal to or greater than a threshold (step S45). When it is determined that the same change point is not calculated above the threshold (step S45: No), the process returns to step S41, and the subsequent processes are repeated.

  On the other hand, if it is determined in step S45 that the same change point has been calculated above the threshold (step S45: Yes), the band calculation unit 65 indicates the change point determined to have been calculated above the threshold in the process of step S45. Packet information of the estimated packet to be obtained is acquired (step S46). Then, the bandwidth calculating unit 65 calculates an available bandwidth using the packet information acquired in the process of step S46 (step S47). After the process of step S47, the band estimation process of the receiving device 12 ends.

  Thus, the receiving device 12 counts the calculated number of change points, and when the same change point is calculated more than the preset number of times, the reception device 12 calculates the band using the change point. A reliable change point can be found before the final packet arrives. As a result, the band estimation accuracy can be improved and the band estimation process of the communication network 13 can be completed in a short time.

<Third Embodiment>
Next, an information processing system according to a third embodiment of the present invention will be described with reference to FIG.
An information processing system 201 according to the third embodiment
A transmission control unit 221 (estimation packet transmission means) is provided that transmits a plurality of estimation packets having packet sizes set in advance to a receiving device 212 connected via the network 213 at a preset transmission interval. A transmission device 211 and a reception device 212;
The receiving device 212 is
A reception control unit 231 (estimation packet receiving means) that receives the estimation packet transmitted from the transmission control unit 221;
A packet information acquisition unit 232 (packet information acquisition unit) for acquiring the reception time and the packet size of the estimation packet received by the reception control unit 231;
Based on the reception times of the first and last estimation packets received among the plurality of estimation packets received by the reception control unit 231, the reception intervals of the estimation packets transmitted before and after each other start to change. A change point calculation unit 233 (delay start packet detection means) for detecting the estimation packet as a delay start packet;
A bandwidth calculation unit 234 (bandwidth calculation means) that calculates the bandwidth of the network 213 using the packet size of the delay start packet detected by the change point calculation unit 233;
Is provided.

  With the above-described configuration, first, the transmission device 211 transmits a plurality of estimation packets, in which packet sizes are set in advance, to the reception device 212 connected via the network 213 at a preset transmission interval. Then, the reception device 212 detects a delay start packet based on the reception times of the first and last received estimation packets among the plurality of received estimation packets. Subsequently, the reception device 212 calculates a bandwidth using the packet size of the detected delay start packet. As a result, even when the estimation packet transmitted from the transmission apparatus 211 is affected by noise or the like in the network, the reception interval is used by using the reception times of the first and last estimation packets so that the influence of noise or the like is reduced. Since the estimation packet that starts to change (delay starts) is detected, the estimation accuracy of the bandwidth of the network 213 can be improved.

  Although the present invention has been described with reference to the above embodiment, the present invention is not limited to the above-described embodiment. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

  In the present invention, the band to be estimated is not limited to the available band but may be a physical band. The present invention is not limited to these, and may be effective throughput of TCP (Transmission Control Protocol) or UDP (User Datagram Protocol).

  Further, in the present invention, the packet size and the transmission interval may be fixed or variable. In any case, the above formula can be used with appropriate modifications.

<Appendix>
Part or all of the above-described embodiment can be described as in the following supplementary notes. The outline of the configuration of the information processing apparatus and the like in the present invention will be described below. However, the present invention is not limited to the following configuration.

(Appendix 1)
A transmission apparatus comprising estimation packet transmitting means for transmitting a plurality of estimation packets having packet sizes set in advance to a reception apparatus connected via a network at a predetermined transmission interval; and the reception apparatus; With
The receiving device is:
An estimation packet receiving means for receiving the estimation packet transmitted from the estimation packet transmitting means;
Packet information acquisition means for acquiring the reception time and packet size of the estimation packet received by the estimation packet reception means;
Reception of estimation packets transmitted back and forth based on the reception times of the estimation packet received first and last among the plurality of estimation packets received by the estimation packet receiving means A delay start packet detecting means for detecting an estimation packet whose interval starts to change as a delay start packet;
Bandwidth calculation means for calculating the bandwidth of the network using the packet size of the delay start packet detected by the delay start packet detection means;
An information processing system comprising:

  With the above configuration, first, the transmission apparatus transmits a plurality of estimation packets having packet sizes set in advance to a reception apparatus connected via the network at a predetermined transmission interval. Then, the receiving device detects a delay start packet based on the reception times of the first and last received estimation packets among the plurality of received estimation packets. Subsequently, the receiving device calculates a bandwidth using the packet size of the detected delay start packet. As a result, even when the estimation packet transmitted from the transmission device is affected by noise or the like in the communication network, the reception interval is used by using the reception times of the first and last estimation packets so that the influence of noise or the like is reduced. Is detected (the delay starts), so that the estimation accuracy of the network bandwidth can be improved.

(Appendix 2)
An information processing system according to attachment 1, wherein
The estimation packet receiving means receives all of the plurality of estimation packets preset from the estimation packet transmission means,
The delay start packet detecting means, after receiving all the estimation packets by the estimation packet receiving means, determines the delay start packet based on the reception times of the estimation packets received first and last. To detect,
Information processing system.

  With the above configuration, the packet information acquisition unit further acquires the transmission time of the estimation packet. The delay start packet detection means detects the delay start packet based on the reception times of the first and last estimation packets received after receiving a plurality of preset estimation packets. As described above, since the delay start packet is detected by using the reception time of the first and last estimation packets that are least affected by noise or the like, the network bandwidth can be estimated with higher accuracy.

(Appendix 3)
An information processing system according to attachment 1, wherein
The delay start packet detection means receives the estimation packet received first and last among the plurality of estimation packets received each time the estimation packet reception means receives the estimation packet. And detecting the delayed start packet based on
The bandwidth calculation means calculates the bandwidth of the network using the packet size of the delay start packet when the number of detections of the same delay start packet detected by the delay start packet detection means is equal to or greater than a preset threshold. calculate,
Information processing system.

  With the above configuration, the packet information acquisition unit further acquires the transmission time of the estimation packet. The delay start packet detecting means detects the delay start packet based on the reception time of the first and last received estimation packets among the plurality of received estimation packets each time the estimation packet sequence is received. To do. The bandwidth calculating means calculates the network bandwidth using the packet size of the delay start packet when the detected number of detected same delay start packets is equal to or greater than a preset threshold value. In this way, the network bandwidth is calculated using the packet size of the delay start packet detected a sufficient number of times, so the network bandwidth is calculated before receiving all the estimation packets transmitted from the transmitter. Therefore, it is possible to estimate a highly accurate band in a short time.

(Appendix 4)
An information processing system according to any one of appendices 1 to 3,
The packet information acquisition means further acquires the transmission time of the estimation packet,
The delay start packet detection means includes a reception interval obtained by subtracting the reception time of the first estimation packet from the reception time of the last estimation packet among the plurality of estimation packets received by the estimation packet reception means. The difference between the transmission time obtained by subtracting the transmission time of the first estimation packet from the transmission time of the last estimation packet is calculated as a packet delay accumulated value representing the accumulated value of the delay time required for the transmission of the estimation packet. And detecting the delay start packet based on the calculated packet delay accumulated value,
Information processing system.

  With the above-described configuration, the delay start packet detecting unit receives a reception interval obtained by subtracting the reception time of the first estimation packet from the reception time of the last estimation packet among the plurality of estimation packets received by the estimation packet reception unit. And the transmission interval obtained by subtracting the transmission time of the first estimation packet from the transmission time of the last estimation packet is calculated as a packet delay accumulated value. Then, the change point calculation unit 64 detects the delay start packet based on the accumulated packet delay value that represents the accumulated delay time required for the transmission of the estimated packet. Therefore, the delay start packet detecting means can calculate the change point based on the packet information of the first and last estimation packets that are not easily affected by noise or the like, so that the delay start packet can be detected with high accuracy. it can.

前記推定用パケットの送信にかかる遅延時間が増加し始める変化点ｋを算出する、
情報処理システム。 (Appendix 5)
An information processing system according to attachment 4, wherein
The delay start packet detecting means is configured such that the number n of the estimation packets received by the estimation packet receiving means, the physical bandwidth C of the network, the cumulative packet delay value Q (n), and the increase amount are constant. The following equation 12 using the packet increase size ΔP of the estimation packet to be

Calculating a change point k at which the delay time for transmission of the estimation packet starts to increase;
Information processing system.

(Appendix 6)
Estimating packet receiving means for receiving the estimating packet from a transmitting apparatus that transmits a plurality of estimating packets having packet sizes set in advance to a receiving apparatus connected via a network at a preset transmission interval When,
Packet information acquisition means for acquiring, as packet information, the reception time and packet size of the estimation packet received by the estimation packet reception means;
Of the plurality of estimation packets received by the estimation packet receiving means, based on the packet information of the estimation packet received first and last, the estimation packets transmitted back and forth with each other Delay start packet detecting means for detecting an estimation packet whose reception interval starts to change as a delay start packet;
Bandwidth calculation means for calculating the bandwidth of the network using the packet size of the delay start packet detected by the delay start packet detection means;
An information processing apparatus comprising:

(Appendix 7)
An information processing apparatus according to appendix 6, wherein
The estimation packet receiving means receives all of the plurality of estimation packets preset from the estimation packet transmission means,
The delay start packet detecting means receives all the estimation packets at the estimation packet receiving means, and then transmits the estimation packet received at the first time and the reception time, and the estimation packet received last. Detecting the delay start packet based on a packet transmission time and a reception time;
Information processing device.

(Appendix 8)
Receiving the estimation packet from a transmission device that transmits a plurality of estimation packets having packet sizes set in advance to a reception device connected via a network at a preset transmission interval;
Obtaining the reception time and packet size of the received estimation packet as packet information,
Based on the packet information of the first and last received estimation packets among the plurality of received estimation packets, the estimation interval at which the reception interval with the estimation packets transmitted back and forth starts to change Detect the packet as a delayed start packet,
A bandwidth is calculated using the packet size of the detected delay start packet.
Information processing method.

(Appendix 9)
An information processing method according to attachment 8, wherein
Receiving all the plurality of estimation packets set in advance;
After receiving all the estimation packets, start delay based on the transmission time and reception time of the estimation packet received first and the transmission time and reception time of the estimation packet received last Detect packets,
Information processing method.

(Appendix 10)
In the information processing device,
Estimating packet receiving means for receiving the estimating packet from a transmitting apparatus that transmits a plurality of estimating packets having packet sizes set in advance to a receiving apparatus connected via a network at a preset transmission interval When,
Packet information acquisition means for acquiring, as packet information, the reception time and packet size of the estimation packet received by the estimation packet reception means;
Of the plurality of estimation packets received by the estimation packet receiving means, based on the packet information of the estimation packet received first and last, the estimation packets transmitted back and forth with each other Delay start packet detecting means for detecting an estimation packet whose reception interval starts to change as a delay start packet;
Bandwidth calculating means for calculating a bandwidth using the packet size of the delay start packet detected by the delay start packet detecting means;
A program to realize

DESCRIPTION OF SYMBOLS 1 Information processing system 11 Transmission apparatus 12 Reception apparatus 13 Communication network 22 Memory 23 Communication part 24 Storage part 31 Operation part 32 Memory 33 Communication part 34 Storage part 51 Estimation packet generation part 52 Transmission control part 61 Reception control part 62 Packet information acquisition Unit 63 storage control unit 64 change point calculation unit 65 band calculation unit 101 information processing system 111 change point counting unit 201 information processing system 211 transmission device 212 reception device 213 network 221 transmission control unit 231 reception control unit 232 packet information acquisition unit 233 change Point calculation unit 234 Band calculation unit

Claims (10)

A transmission apparatus comprising estimation packet transmitting means for transmitting a plurality of estimation packets having packet sizes set in advance to a reception apparatus connected via a network at a predetermined transmission interval; and the reception apparatus; With
The receiving device is:
An estimation packet receiving means for receiving the estimation packet transmitted from the estimation packet transmitting means;
Packet information acquisition means for acquiring the reception time and packet size of the estimation packet received by the estimation packet reception means;
Reception of estimation packets transmitted back and forth based on the reception times of the estimation packet received first and last among the plurality of estimation packets received by the estimation packet receiving means A delay start packet detecting means for detecting an estimation packet whose interval starts to change as a delay start packet;
Bandwidth calculation means for calculating the bandwidth of the network using the packet size of the delay start packet detected by the delay start packet detection means;
An information processing system comprising: The information processing system according to claim 1,
The estimation packet receiving means receives all of the plurality of estimation packets preset from the estimation packet transmission means,
The delay start packet detecting means, after receiving all the estimation packets by the estimation packet receiving means, determines the delay start packet based on the reception times of the estimation packets received first and last. To detect,
Information processing system. The information processing system according to claim 1,
The delay start packet detection means receives the estimation packet received first and last among the plurality of estimation packets received each time the estimation packet reception means receives the estimation packet. And detecting the delayed start packet based on
The bandwidth calculation means calculates the bandwidth of the network using the packet size of the delay start packet when the number of detections of the same delay start packet detected by the delay start packet detection means is equal to or greater than a preset threshold. calculate,
Information processing system. An information processing system according to any one of claims 1 to 3,
The packet information acquisition means further acquires the transmission time of the estimation packet,
The delay start packet detection means includes a reception interval obtained by subtracting the reception time of the first estimation packet from the reception time of the last estimation packet among the plurality of estimation packets received by the estimation packet reception means. The difference between the transmission time obtained by subtracting the transmission time of the first estimation packet from the transmission time of the last estimation packet is calculated as a packet delay accumulated value representing the accumulated value of the delay time required for the transmission of the estimation packet. And detecting the delay start packet based on the calculated packet delay accumulated value,
Information processing system. The information processing system according to claim 4,
The delay start packet detecting means is configured such that the number n of the estimation packets received by the estimation packet receiving means, the physical bandwidth C of the network, the cumulative packet delay value Q (n), and the increase amount are constant. The following equation 12 using the packet increase size ΔP of the estimation packet to be

Calculating a change point k at which the delay time for transmission of the estimation packet starts to increase;
Information processing system. Estimating packet receiving means for receiving the estimating packet from a transmitting apparatus that transmits a plurality of estimating packets having packet sizes set in advance to a receiving apparatus connected via a network at a preset transmission interval When,
Packet information acquisition means for acquiring, as packet information, the reception time and packet size of the estimation packet received by the estimation packet reception means;
Of the plurality of estimation packets received by the estimation packet receiving means, based on the packet information of the estimation packet received first and last, the estimation packets transmitted back and forth with each other Delay start packet detecting means for detecting an estimation packet whose reception interval starts to change as a delay start packet;
Bandwidth calculation means for calculating the bandwidth of the network using the packet size of the delay start packet detected by the delay start packet detection means;
An information processing apparatus comprising: The information processing apparatus according to claim 6,
The estimation packet receiving means receives all of the plurality of estimation packets preset from the estimation packet transmission means,
The delay start packet detecting means receives all the estimation packets at the estimation packet receiving means, and then transmits the estimation packet received at the first time and the reception time, and the estimation packet received last. Detecting the delay start packet based on a packet transmission time and a reception time;
Information processing device. Receiving the estimation packet from a transmission device that transmits a plurality of estimation packets having packet sizes set in advance to a reception device connected via a network at a preset transmission interval;
Obtaining the reception time and packet size of the received estimation packet as packet information,
Based on the packet information of the first and last received estimation packets among the plurality of received estimation packets, the estimation interval at which the reception interval with the estimation packets transmitted back and forth starts to change Detect the packet as a delayed start packet,
A bandwidth is calculated using the packet size of the detected delay start packet.
Information processing method. The information processing method according to claim 8,
Receiving all the plurality of estimation packets set in advance;
After receiving all the estimation packets, start delay based on the transmission time and reception time of the estimation packet received first and the transmission time and reception time of the estimation packet received last Detect packets,
Information processing method. In the information processing device,
Estimating packet receiving means for receiving the estimating packet from a transmitting apparatus that transmits a plurality of estimating packets having packet sizes set in advance to a receiving apparatus connected via a network at a preset transmission interval When,
Packet information acquisition means for acquiring, as packet information, the reception time and packet size of the estimation packet received by the estimation packet reception means;
Of the plurality of estimation packets received by the estimation packet receiving means, based on the packet information of the estimation packet received first and last, the estimation packets transmitted back and forth with each other Delay start packet detecting means for detecting an estimation packet whose reception interval starts to change as a delay start packet;
Bandwidth calculating means for calculating a bandwidth using the packet size of the delay start packet detected by the delay start packet detecting means;
A program to realize

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